The invention relates to a pressurized percolating filter of the type used for the regeneration of water in aquariums.
The regeneration or purification of water comprises a biological-bacterial filtering, obtained by making the water run through a percolating support or substratus on which aerobic bacteria colonize and decompose polluting substances.
The aerobic bacteria, while biologically decomposing the polluting substances, consume a large quantity of oxygen, making it necessary to provide them with as much oxygen as possible.
In known percolating filters the water, running finely on the substratus, becomes well oxygenated on contact with air present inside the filter. Still, in order to improve the efficiency of the filter it has been considered necessary to increase the oxygenation of the water.
Presently, for this goal an oxygen reactor is used, consisting of an apparatus where the percolating substratus is crossed by the water. In order that the absorption of oxygen is guaranteed to be of the highest possible level, the reactor is permanently fed with new air through an aerator which continuously renews the air. By regulating the flow of both the water and the air, an increase in atmospheric pressure is obtained internally to the filtering chamber which permits a greater solubility of the oxygen in the water, so as to obtain high values of saturation and thus benefit the aerobic bacteria.
However, a percolator filter associated with an oxygen reactor of the type described, even if efficient, is certainly expensive and complex, and limited in its practical application by the necessity to predispose safety systems which intervene in case of malfunctioning of the aerator or other parts of the reactor to prevent the death by asphyxia of the bacterial colony.
The present invention aims to eliminate the above-mentioned inconveniences.
An aim of the present invention is to provide a percolating filter of small dimensions, that is simply constructed, able to provide superior filtering performance, simple in its functioning, and requires little maintenance.